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Synthetic Oil- Weight and interval


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I just switched my 99 Legacy to Mobil One 5w-30 which works fine so far.

 

Two questions:

1. How long a change interval do you think is safe--car is driven mostly on highway with no stop and go.

 

2. Does anyone have experience or advice on the 0-40W weight for winter use? While car is garaged, Cold is extreme in Minnesota

thanks

John

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I have used both Mobil 1 and Amsoil. I use 5w-30 in the winter and 10w-30 in the summer. I live in a Zone 4, so it gets pretty cold. I personally won't go thinner than 5w-30.

 

With Mobil 1 I was changing the oil every 3-4k miles. Now with Amsoil I am changing the oil about every 3 months, or about every 7500 miles. I could go longer, but I think doing so would require oil analysis, and that is almost as much as changing the oil.

 

The engine seems much happier with the Amsoil. The engine is quieter at startup. I can run it for 3 or 4 thousand miles before the color darkens noticably.

 

Regardless of what oil you choose, use a quality oil filter. I really like the Amsoil filters, but I think I should find something cheaper, they are about $11 each.

 

15w-50 year round! Wow!

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I don't have a clue what you're talking about with the zone 4--luckily google does.

 

So, I guess I live in a zone 3a climate. Anyway, the pour temp on 15W-50 (-45 C) is still lower than dino-based 0W. I prefer to have a little viscosity to my oil. Mobil-1 10W-30 always seemed to have the consistancy of water while draining it. :( Any oil with 'energy conserving' on it I don't touch. [paranoia mode off]

 

I've never had sluggish cranking while running 15W-50 and I don't even have a block heater in my sub. YMMV

 

jim

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Mobil 1, all the rest are second best :-)

 

5w-50 in Danish Spring/summer, temps up to +33 celcius

 

0w-40 in winter, where the temp regularly goes below freezing.

 

 

There is a tiny, but noticeable difference in start up: 5w sounds a bit strained on frosty mornings. As soon as I swap to 0w she starts as if it were a warm summer day!

 

6000 mile intervals, which equates to every three months. Car is nearing the 200,000 milestone :D

 

Also have Mobil's finest in the manual transmission :brow:

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I'm running Mobil 1 10W-30 right now, and I change it every 3-4,000 miles. Yes, you CAN run it longer than that, but it doesn't matter how good your oil is, it still gets contaminents in it after a while, and the more often it's changed, the less those contaminents are wreaking havoc on your engine internals.

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I use the OE oil filter, and I would NEVER go for a cheap copy. There is a big difference in the filtering properties of the paper element, not to mention the total surface area. Also, the bypass valve can be relied upon to not open unless the filter really is clogged.

 

I don't doubt that there are even better quality filters out there, Amsoil included, but replacing an OE filter every three months is costly enough :D

 

I am sure Mobil 1 can last 6000 miles under the conditions that I subject it to, don't forget it's only in there for three months, and it's only cold-started once a day since I am on the move all day.

 

I am however VERY sceptical of so called modern car's extended service intervals. Honestly, running the same oil for 20,000 miles??

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I would never run Amsoil for 25k miles as they suggest. To do so safely requires periodic oil analysis, and many engines won't make it that far before the oil requires replacement.

 

I feel pretty comfortable with 7500 miles intervals.

 

I am totally sold on synthetic. When I had the engine apart for head gaskets it was clean as a whistle with very little wear. I was running Mobil 1 at that point.

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Just so you know.

 

4.25 quarts.

 

17mm drain plug wrench (EJ251)

 

(K&N) HP 1004 oil filter (for EJ251) (up to you)

 

2,500 Miles or 3 months. (1,000 miles for me :D )

 

10W-30 Summer

 

5W-30 Winter.

 

Just dont use pennzoil with their wax based oil. Mobil 1 is a great synthetic, when compared to castrol synthetic oil.

 

Oh, and that lil MMO (marvel mystery oil) experiment is a crock of crap, the difference people are feeling is only their oil being changed. Yes, your car will feel alot better after an oil change.

 

 

I miss anything???

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BITOG forum and FAQ's etc will teach you all you want to know about oil, filters both air & oil, greases. additives, engine internal cleaners, fuel system cleaners and much more such as which oil filters have the least pressure drop etc. No flaming and many contributing STLE"s, other highly qualified tribology experts and even Blackstone Analysis and Terry Dyson Analysis are contributors. Sure helped me get my Outback running far better and much better economy too. Also you will learn why Pennzoils new Purebase is generally regarded as one of the top three dino's in the industry (it's a Group II+ basestock) along with Delo 400 and Mobil Delvac 1300 Super. One of the main reasons Shell bought Pennzoil/Quaker State. Wax based it certainly isn't (it's parafinic) as are Conoco, Chevron, Havoline etc Group II+ basestock products but it's far too complicated to explain here, and requires somebody far more knowledgeable than I to do so correctly. http://WWW.BOBISTHEOILGUY.COM for more

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Exactly. Till I found BITOG I wouldn't have touched Pennzoil even though it's everywhere here in Aussie just because of all the old wives tales. The new Pennzoil Quaker State base oil refinery was a joint efort with ConocoPhilips called Excel Paralubes that gave rise to the Purebase range, a whole new ball game. Conoco Hydroclear same stuff I believe. As part of Shells takeover of PQS a condition was that it's 50% share of Excel Paralubes had to be sold and Flint Hills Resources LP are the purchaser. Purebase is a Group II+ basestock, excellent additive package and now a healthy dose of moly. Hard to beat and excellent value for money. I currently use 5W30 version in my OB doing an after Auto-Rx rinse. FWIW It's the last time I will use an XW30 in any vehicle I own, the OB sounds like a tin can full of ball bearings, so back to XW40 soon.

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Sprintman: Why so hard on M1? The "original" from the late eighties kicked some serious behind. I can't believe they would have made an inferior product??

 

Except maybe if they decided to exploit a reputation and make some extra money for themselves. :madder:

 

 

I still run M1..:D

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Trisyn was somewhat lacking in barrier lubrication. Supersyn UOA's are so much better across the board. Now contains moly which is good. About the best OTC syn around these days. You really can't go wrong with the current M1 but they are formulated at the low end of the 30W range which causes consumption problems in many vehicles. Why Mobil don't have a 5W40 M1 I dont understand. Many Sube owners use Delvac 1 (5W40) which as a fleet oil is CI-4 and SL rated. A very shear stable product.

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